Cream the butter and margarine.,Add sugar gradually; continue beating.,Add eggs, one at a time; mix well.,______,Add milk after each addition of flour.,Grease and flour 3 layer cake pans.,Bake in a 300° oven until browned and shrinks from sides of pan.,Remove cake from pans; place on wire racks. When cool, spread with your favorite jelly.,Spread lemon frosting on top and sides.